Alright, let's solve this math problem step by step. First, we have the number 644. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 462. So, we're going to take the number 644 and add it to itself 462 times.
Step 1: 0 + 644 = 644
Step 2: 644 + 644 = 1288
Step 3: 1288 + 644 = 1932
Step 4: 1932 + 644 = 2576
Step 5: 2576 + 644 = 3220
Step 6: 3220 + 644 = 3864
Step 7: 3864 + 644 = 4508
Step 8: 4508 + 644 = 5152
Step 9: 5152 + 644 = 5796
Step 10: 5796 + 644 = 6440
Step 11: 6440 + 644 = 7084
Step 12: 7084 + 644 = 7728
Step 13: 7728 + 644 = 8372
Step 14: 8372 + 644 = 9016
Step 15: 9016 + 644 = 9660
Step 16: 9660 + 644 = 10304
Step 17: 10304 + 644 = 10948
Step 18: 10948 + 644 = 11592
Step 19: 11592 + 644 = 12236
Step 20: 12236 + 644 = 12880
Step 21: 12880 + 644 = 13524
Step 22: 13524 + 644 = 14168
Step 23: 14168 + 644 = 14812
Step 24: 14812 + 644 = 15456
Step 25: 15456 + 644 = 16100
Step 26: 16100 + 644 = 16744
Step 27: 16744 + 644 = 17388
Step 28: 17388 + 644 = 18032
Step 29: 18032 + 644 = 18676
Step 30: 18676 + 644 = 19320
Step 31: 19320 + 644 = 19964
Step 32: 19964 + 644 = 20608
Step 33: 20608 + 644 = 21252
Step 34: 21252 + 644 = 21896
Step 35: 21896 + 644 = 22540
Step 36: 22540 + 644 = 23184
Step 37: 23184 + 644 = 23828
Step 38: 23828 + 644 = 24472
Step 39: 24472 + 644 = 25116
Step 40: 25116 + 644 = 25760
Step 41: 25760 + 644 = 26404
Step 42: 26404 + 644 = 27048
Step 43: 27048 + 644 = 27692
Step 44: 27692 + 644 = 28336
Step 45: 28336 + 644 = 28980
Step 46: 28980 + 644 = 29624
Step 47: 29624 + 644 = 30268
Step 48: 30268 + 644 = 30912
Step 49: 30912 + 644 = 31556
Step 50: 31556 + 644 = 32200
Step 51: 32200 + 644 = 32844
Step 52: 32844 + 644 = 33488
Step 53: 33488 + 644 = 34132
Step 54: 34132 + 644 = 34776
Step 55: 34776 + 644 = 35420
Step 56: 35420 + 644 = 36064
Step 57: 36064 + 644 = 36708
Step 58: 36708 + 644 = 37352
Step 59: 37352 + 644 = 37996
Step 60: 37996 + 644 = 38640
Step 61: 38640 + 644 = 39284
Step 62: 39284 + 644 = 39928
Step 63: 39928 + 644 = 40572
Step 64: 40572 + 644 = 41216
Step 65: 41216 + 644 = 41860
Step 66: 41860 + 644 = 42504
Step 67: 42504 + 644 = 43148
Step 68: 43148 + 644 = 43792
Step 69: 43792 + 644 = 44436
Step 70: 44436 + 644 = 45080
Step 71: 45080 + 644 = 45724
Step 72: 45724 + 644 = 46368
Step 73: 46368 + 644 = 47012
Step 74: 47012 + 644 = 47656
Step 75: 47656 + 644 = 48300
Step 76: 48300 + 644 = 48944
Step 77: 48944 + 644 = 49588
Step 78: 49588 + 644 = 50232
Step 79: 50232 + 644 = 50876
Step 80: 50876 + 644 = 51520
Step 81: 51520 + 644 = 52164
Step 82: 52164 + 644 = 52808
Step 83: 52808 + 644 = 53452
Step 84: 53452 + 644 = 54096
Step 85: 54096 + 644 = 54740
Step 86: 54740 + 644 = 55384
Step 87: 55384 + 644 = 56028
Step 88: 56028 + 644 = 56672
Step 89: 56672 + 644 = 57316
Step 90: 57316 + 644 = 57960
Step 91: 57960 + 644 = 58604
Step 92: 58604 + 644 = 59248
Step 93: 59248 + 644 = 59892
Step 94: 59892 + 644 = 60536
Step 95: 60536 + 644 = 61180
Step 96: 61180 + 644 = 61824
Step 97: 61824 + 644 = 62468
Step 98: 62468 + 644 = 63112
Step 99: 63112 + 644 = 63756
Step 100: 63756 + 644 = 64400
Step 101: 64400 + 644 = 65044
Step 102: 65044 + 644 = 65688
Step 103: 65688 + 644 = 66332
Step 104: 66332 + 644 = 66976
Step 105: 66976 + 644 = 67620
Step 106: 67620 + 644 = 68264
Step 107: 68264 + 644 = 68908
Step 108: 68908 + 644 = 69552
Step 109: 69552 + 644 = 70196
Step 110: 70196 + 644 = 70840
Step 111: 70840 + 644 = 71484
Step 112: 71484 + 644 = 72128
Step 113: 72128 + 644 = 72772
Step 114: 72772 + 644 = 73416
Step 115: 73416 + 644 = 74060
Step 116: 74060 + 644 = 74704
Step 117: 74704 + 644 = 75348
Step 118: 75348 + 644 = 75992
Step 119: 75992 + 644 = 76636
Step 120: 76636 + 644 = 77280
Step 121: 77280 + 644 = 77924
Step 122: 77924 + 644 = 78568
Step 123: 78568 + 644 = 79212
Step 124: 79212 + 644 = 79856
Step 125: 79856 + 644 = 80500
Step 126: 80500 + 644 = 81144
Step 127: 81144 + 644 = 81788
Step 128: 81788 + 644 = 82432
Step 129: 82432 + 644 = 83076
Step 130: 83076 + 644 = 83720
Step 131: 83720 + 644 = 84364
Step 132: 84364 + 644 = 85008
Step 133: 85008 + 644 = 85652
Step 134: 85652 + 644 = 86296
Step 135: 86296 + 644 = 86940
Step 136: 86940 + 644 = 87584
Step 137: 87584 + 644 = 88228
Step 138: 88228 + 644 = 88872
Step 139: 88872 + 644 = 89516
Step 140: 89516 + 644 = 90160
Step 141: 90160 + 644 = 90804
Step 142: 90804 + 644 = 91448
Step 143: 91448 + 644 = 92092
Step 144: 92092 + 644 = 92736
Step 145: 92736 + 644 = 93380
Step 146: 93380 + 644 = 94024
Step 147: 94024 + 644 = 94668
Step 148: 94668 + 644 = 95312
Step 149: 95312 + 644 = 95956
Step 150: 95956 + 644 = 96600
Step 151: 96600 + 644 = 97244
Step 152: 97244 + 644 = 97888
Step 153: 97888 + 644 = 98532
Step 154: 98532 + 644 = 99176
Step 155: 99176 + 644 = 99820
Step 156: 99820 + 644 = 100464
Step 157: 100464 + 644 = 101108
Step 158: 101108 + 644 = 101752
Step 159: 101752 + 644 = 102396
Step 160: 102396 + 644 = 103040
Step 161: 103040 + 644 = 103684
Step 162: 103684 + 644 = 104328
Step 163: 104328 + 644 = 104972
Step 164: 104972 + 644 = 105616
Step 165: 105616 + 644 = 106260
Step 166: 106260 + 644 = 106904
Step 167: 106904 + 644 = 107548
Step 168: 107548 + 644 = 108192
Step 169: 108192 + 644 = 108836
Step 170: 108836 + 644 = 109480
Step 171: 109480 + 644 = 110124
Step 172: 110124 + 644 = 110768
Step 173: 110768 + 644 = 111412
Step 174: 111412 + 644 = 112056
Step 175: 112056 + 644 = 112700
Step 176: 112700 + 644 = 113344
Step 177: 113344 + 644 = 113988
Step 178: 113988 + 644 = 114632
Step 179: 114632 + 644 = 115276
Step 180: 115276 + 644 = 115920
Step 181: 115920 + 644 = 116564
Step 182: 116564 + 644 = 117208
Step 183: 117208 + 644 = 117852
Step 184: 117852 + 644 = 118496
Step 185: 118496 + 644 = 119140
Step 186: 119140 + 644 = 119784
Step 187: 119784 + 644 = 120428
Step 188: 120428 + 644 = 121072
Step 189: 121072 + 644 = 121716
Step 190: 121716 + 644 = 122360
Step 191: 122360 + 644 = 123004
Step 192: 123004 + 644 = 123648
Step 193: 123648 + 644 = 124292
Step 194: 124292 + 644 = 124936
Step 195: 124936 + 644 = 125580
Step 196: 125580 + 644 = 126224
Step 197: 126224 + 644 = 126868
Step 198: 126868 + 644 = 127512
Step 199: 127512 + 644 = 128156
Step 200: 128156 + 644 = 128800
Step 201: 128800 + 644 = 129444
Step 202: 129444 + 644 = 130088
Step 203: 130088 + 644 = 130732
Step 204: 130732 + 644 = 131376
Step 205: 131376 + 644 = 132020
Step 206: 132020 + 644 = 132664
Step 207: 132664 + 644 = 133308
Step 208: 133308 + 644 = 133952
Step 209: 133952 + 644 = 134596
Step 210: 134596 + 644 = 135240
Step 211: 135240 + 644 = 135884
Step 212: 135884 + 644 = 136528
Step 213: 136528 + 644 = 137172
Step 214: 137172 + 644 = 137816
Step 215: 137816 + 644 = 138460
Step 216: 138460 + 644 = 139104
Step 217: 139104 + 644 = 139748
Step 218: 139748 + 644 = 140392
Step 219: 140392 + 644 = 141036
Step 220: 141036 + 644 = 141680
Step 221: 141680 + 644 = 142324
Step 222: 142324 + 644 = 142968
Step 223: 142968 + 644 = 143612
Step 224: 143612 + 644 = 144256
Step 225: 144256 + 644 = 144900
Step 226: 144900 + 644 = 145544
Step 227: 145544 + 644 = 146188
Step 228: 146188 + 644 = 146832
Step 229: 146832 + 644 = 147476
Step 230: 147476 + 644 = 148120
Step 231: 148120 + 644 = 148764
Step 232: 148764 + 644 = 149408
Step 233: 149408 + 644 = 150052
Step 234: 150052 + 644 = 150696
Step 235: 150696 + 644 = 151340
Step 236: 151340 + 644 = 151984
Step 237: 151984 + 644 = 152628
Step 238: 152628 + 644 = 153272
Step 239: 153272 + 644 = 153916
Step 240: 153916 + 644 = 154560
Step 241: 154560 + 644 = 155204
Step 242: 155204 + 644 = 155848
Step 243: 155848 + 644 = 156492
Step 244: 156492 + 644 = 157136
Step 245: 157136 + 644 = 157780
Step 246: 157780 + 644 = 158424
Step 247: 158424 + 644 = 159068
Step 248: 159068 + 644 = 159712
Step 249: 159712 + 644 = 160356
Step 250: 160356 + 644 = 161000
Step 251: 161000 + 644 = 161644
Step 252: 161644 + 644 = 162288
Step 253: 162288 + 644 = 162932
Step 254: 162932 + 644 = 163576
Step 255: 163576 + 644 = 164220
Step 256: 164220 + 644 = 164864
Step 257: 164864 + 644 = 165508
Step 258: 165508 + 644 = 166152
Step 259: 166152 + 644 = 166796
Step 260: 166796 + 644 = 167440
Step 261: 167440 + 644 = 168084
Step 262: 168084 + 644 = 168728
Step 263: 168728 + 644 = 169372
Step 264: 169372 + 644 = 170016
Step 265: 170016 + 644 = 170660
Step 266: 170660 + 644 = 171304
Step 267: 171304 + 644 = 171948
Step 268: 171948 + 644 = 172592
Step 269: 172592 + 644 = 173236
Step 270: 173236 + 644 = 173880
Step 271: 173880 + 644 = 174524
Step 272: 174524 + 644 = 175168
Step 273: 175168 + 644 = 175812
Step 274: 175812 + 644 = 176456
Step 275: 176456 + 644 = 177100
Step 276: 177100 + 644 = 177744
Step 277: 177744 + 644 = 178388
Step 278: 178388 + 644 = 179032
Step 279: 179032 + 644 = 179676
Step 280: 179676 + 644 = 180320
Step 281: 180320 + 644 = 180964
Step 282: 180964 + 644 = 181608
Step 283: 181608 + 644 = 182252
Step 284: 182252 + 644 = 182896
Step 285: 182896 + 644 = 183540
Step 286: 183540 + 644 = 184184
Step 287: 184184 + 644 = 184828
Step 288: 184828 + 644 = 185472
Step 289: 185472 + 644 = 186116
Step 290: 186116 + 644 = 186760
Step 291: 186760 + 644 = 187404
Step 292: 187404 + 644 = 188048
Step 293: 188048 + 644 = 188692
Step 294: 188692 + 644 = 189336
Step 295: 189336 + 644 = 189980
Step 296: 189980 + 644 = 190624
Step 297: 190624 + 644 = 191268
Step 298: 191268 + 644 = 191912
Step 299: 191912 + 644 = 192556
Step 300: 192556 + 644 = 193200
Step 301: 193200 + 644 = 193844
Step 302: 193844 + 644 = 194488
Step 303: 194488 + 644 = 195132
Step 304: 195132 + 644 = 195776
Step 305: 195776 + 644 = 196420
Step 306: 196420 + 644 = 197064
Step 307: 197064 + 644 = 197708
Step 308: 197708 + 644 = 198352
Step 309: 198352 + 644 = 198996
Step 310: 198996 + 644 = 199640
Step 311: 199640 + 644 = 200284
Step 312: 200284 + 644 = 200928
Step 313: 200928 + 644 = 201572
Step 314: 201572 + 644 = 202216
Step 315: 202216 + 644 = 202860
Step 316: 202860 + 644 = 203504
Step 317: 203504 + 644 = 204148
Step 318: 204148 + 644 = 204792
Step 319: 204792 + 644 = 205436
Step 320: 205436 + 644 = 206080
Step 321: 206080 + 644 = 206724
Step 322: 206724 + 644 = 207368
Step 323: 207368 + 644 = 208012
Step 324: 208012 + 644 = 208656
Step 325: 208656 + 644 = 209300
Step 326: 209300 + 644 = 209944
Step 327: 209944 + 644 = 210588
Step 328: 210588 + 644 = 211232
Step 329: 211232 + 644 = 211876
Step 330: 211876 + 644 = 212520
Step 331: 212520 + 644 = 213164
Step 332: 213164 + 644 = 213808
Step 333: 213808 + 644 = 214452
Step 334: 214452 + 644 = 215096
Step 335: 215096 + 644 = 215740
Step 336: 215740 + 644 = 216384
Step 337: 216384 + 644 = 217028
Step 338: 217028 + 644 = 217672
Step 339: 217672 + 644 = 218316
Step 340: 218316 + 644 = 218960
Step 341: 218960 + 644 = 219604
Step 342: 219604 + 644 = 220248
Step 343: 220248 + 644 = 220892
Step 344: 220892 + 644 = 221536
Step 345: 221536 + 644 = 222180
Step 346: 222180 + 644 = 222824
Step 347: 222824 + 644 = 223468
Step 348: 223468 + 644 = 224112
Step 349: 224112 + 644 = 224756
Step 350: 224756 + 644 = 225400
Step 351: 225400 + 644 = 226044
Step 352: 226044 + 644 = 226688
Step 353: 226688 + 644 = 227332
Step 354: 227332 + 644 = 227976
Step 355: 227976 + 644 = 228620
Step 356: 228620 + 644 = 229264
Step 357: 229264 + 644 = 229908
Step 358: 229908 + 644 = 230552
Step 359: 230552 + 644 = 231196
Step 360: 231196 + 644 = 231840
Step 361: 231840 + 644 = 232484
Step 362: 232484 + 644 = 233128
Step 363: 233128 + 644 = 233772
Step 364: 233772 + 644 = 234416
Step 365: 234416 + 644 = 235060
Step 366: 235060 + 644 = 235704
Step 367: 235704 + 644 = 236348
Step 368: 236348 + 644 = 236992
Step 369: 236992 + 644 = 237636
Step 370: 237636 + 644 = 238280
Step 371: 238280 + 644 = 238924
Step 372: 238924 + 644 = 239568
Step 373: 239568 + 644 = 240212
Step 374: 240212 + 644 = 240856
Step 375: 240856 + 644 = 241500
Step 376: 241500 + 644 = 242144
Step 377: 242144 + 644 = 242788
Step 378: 242788 + 644 = 243432
Step 379: 243432 + 644 = 244076
Step 380: 244076 + 644 = 244720
Step 381: 244720 + 644 = 245364
Step 382: 245364 + 644 = 246008
Step 383: 246008 + 644 = 246652
Step 384: 246652 + 644 = 247296
Step 385: 247296 + 644 = 247940
Step 386: 247940 + 644 = 248584
Step 387: 248584 + 644 = 249228
Step 388: 249228 + 644 = 249872
Step 389: 249872 + 644 = 250516
Step 390: 250516 + 644 = 251160
Step 391: 251160 + 644 = 251804
Step 392: 251804 + 644 = 252448
Step 393: 252448 + 644 = 253092
Step 394: 253092 + 644 = 253736
Step 395: 253736 + 644 = 254380
Step 396: 254380 + 644 = 255024
Step 397: 255024 + 644 = 255668
Step 398: 255668 + 644 = 256312
Step 399: 256312 + 644 = 256956
Step 400: 256956 + 644 = 257600
Step 401: 257600 + 644 = 258244
Step 402: 258244 + 644 = 258888
Step 403: 258888 + 644 = 259532
Step 404: 259532 + 644 = 260176
Step 405: 260176 + 644 = 260820
Step 406: 260820 + 644 = 261464
Step 407: 261464 + 644 = 262108
Step 408: 262108 + 644 = 262752
Step 409: 262752 + 644 = 263396
Step 410: 263396 + 644 = 264040
Step 411: 264040 + 644 = 264684
Step 412: 264684 + 644 = 265328
Step 413: 265328 + 644 = 265972
Step 414: 265972 + 644 = 266616
Step 415: 266616 + 644 = 267260
Step 416: 267260 + 644 = 267904
Step 417: 267904 + 644 = 268548
Step 418: 268548 + 644 = 269192
Step 419: 269192 + 644 = 269836
Step 420: 269836 + 644 = 270480
Step 421: 270480 + 644 = 271124
Step 422: 271124 + 644 = 271768
Step 423: 271768 + 644 = 272412
Step 424: 272412 + 644 = 273056
Step 425: 273056 + 644 = 273700
Step 426: 273700 + 644 = 274344
Step 427: 274344 + 644 = 274988
Step 428: 274988 + 644 = 275632
Step 429: 275632 + 644 = 276276
Step 430: 276276 + 644 = 276920
Step 431: 276920 + 644 = 277564
Step 432: 277564 + 644 = 278208
Step 433: 278208 + 644 = 278852
Step 434: 278852 + 644 = 279496
Step 435: 279496 + 644 = 280140
Step 436: 280140 + 644 = 280784
Step 437: 280784 + 644 = 281428
Step 438: 281428 + 644 = 282072
Step 439: 282072 + 644 = 282716
Step 440: 282716 + 644 = 283360
Step 441: 283360 + 644 = 284004
Step 442: 284004 + 644 = 284648
Step 443: 284648 + 644 = 285292
Step 444: 285292 + 644 = 285936
Step 445: 285936 + 644 = 286580
Step 446: 286580 + 644 = 287224
Step 447: 287224 + 644 = 287868
Step 448: 287868 + 644 = 288512
Step 449: 288512 + 644 = 289156
Step 450: 289156 + 644 = 289800
Step 451: 289800 + 644 = 290444
Step 452: 290444 + 644 = 291088
Step 453: 291088 + 644 = 291732
Step 454: 291732 + 644 = 292376
Step 455: 292376 + 644 = 293020
Step 456: 293020 + 644 = 293664
Step 457: 293664 + 644 = 294308
Step 458: 294308 + 644 = 294952
Step 459: 294952 + 644 = 295596
Step 460: 295596 + 644 = 296240
Step 461: 296240 + 644 = 296884
Step 462: 296884 + 644 = 297528

So, 644*462 = 297528